Week 3 -Vascular Disease Flashcards
Define Aneurysm
A localised dilation or out-pouching of a vessel wall
What causes an Aneurysm
Atherosclerosis:
- The most common cause
- Plaque erodes the vessel wall leading to inflammation which causes weakening of the vessel
Hypertension:
- Increasing wall stress which contributes to aneurysm formation.
Why are Aneurysm commonly found in the Aorta
- 75% of all aneurysm occur in the abdominal aorta due to the constant stress on the vessel wall
- The high pressure of the arterial system results to the bulging of the vessel.
- Tend to enlarge over time (asymptomatic)
What happens when an Aneurysm leaks
- Painful
- Dysphagia (difficulty swallowing)
- Dysnpoea
- Causes pressure on surrounding organs
- When impairs flow > ischaemia
What are the treatments for Aneurysm?
Slow-growing Aortic Aneurysms:
- Smoking cessation
- Reducing blood pressure and blood volume.
Dilating rapidly/large:
- Surgical intervention - replacement with a prosthetic graft
Explain how a Thrombus forms
- It develops when intravascular conditions promote activation of coagulation or when there is stasis of blood flow & platelets proteins and cells stick together.
- Irritation
- Inflammation
- Traumatic injury
- Infection
- Low blood pressures that cause blood stasis and pooling within the vessels.
What are the risks of Thrombus
- Thrombus may grow large which can occlude the artery resulting in tissue ischaemia
- The thrombus may dislodge travelling through the vascular system and occludes a distal systemic vascular bed
How do we diagnose a Thrombus
Doppler ultrasonography, angiography
What are the two treatments for Thrombus
- Heparin
- Warfarin
- Thrombin inhibitors (i.e. Factor Xa inhibitors)
- Thrombolytics.
- A balloon-tipped catheter can also be used to remove or compress an arterial thrombus.
What is an Embolism
- The obstruction of a vessel by anembolus
- An embolus travels in the bloodstream until it reaches a vessel through which it cannot fit
- Lodge in a systemic or pulmonary vessel
What does an Embolus consists of:
- Aggregate of fat
- Aggregate of amniotic fluid
- Cancer cells
- Bacteria
- Foreign substance
- Air bubble
- Dislodged thrombus
Define Arteriosclerosis
A chronic disease of the arterial system characterised by abnormal thickening and hardening ofthe vessel walls.
What is the process of arterial remodelling in atherosclerosis?
- Smooth muscle cells and collagen fibres migrate into the tunica intima
- Causing it to stiffen and thicken, gradually narrowing the arterial lumen
Define Atherosclerosis
- A specific kind of arteriosclerosis
- Disease in which plaque (fats, cholesterol and other substances) builds up inside arteries. Over time, plaque hardens and narrows arteries
What causes Atherosclerosis
- Inflammation plays a fundamental role in the initiation and progression
- Begins with injury to the endothelial cells (lining the artery walls)
- Possible causes of endothelial injury:
- Smoking
- Hypertension
Describe the progression of Atherosclerosis
- Damaged endothelium
- Fatty streak - macrophages that engulf LDL
- Fibrous plaque. Raised plaques are visible
- Complicated lesion; Plaque is complicated by thrombus deposition.
What are the risks of Atherosclerosis
- Obstruction can cause tissue infarction, pain and disability
- It can also result to Coronary Heart Disease such as myocardial ischaemia
